Field of the Invention
The present invention relates to a technique for removing an unwanted object from an image with use of a plurality of images shot from different viewpoints.
Description of the Related Art
In recent years, there has been known an image processing technique for removing a predetermined object in a subject with use of images acquired by shooting the subject from a plurality of viewpoints (hereinafter referred to as multi-viewpoint images). For example, Japanese Patent Application Laid-Open No. 2008-117305 discusses a technique for removing an unwanted object in a subject with use of images acquired by a stereo camera. According to the technique discussed in Japanese Patent Application Laid-Open No. 2008-117305, the unwanted object is removed by replacing pixel values in a portion where the subject is hidden by the unwanted object (an occlusion region) based on images acquired from different viewpoints.
When an unwanted object is to be removed with use of images acquired by a twin-lens stereo camera, like the technique discussed in Japanese Patent Application Laid-Open No. 2008-117305, it is difficult to remove a linear unwanted object extending in parallel with a straight line defined by two viewpoints corresponding to the stereo camera. Therefore, a possible solution therefor is to remove the unwanted object by acquiring images with use of an array camera capable of shooting a subject from a larger number of viewpoints to deal with and remove various kinds of unwanted objects. However, when the unwanted object removal processing is performed with use of all the images acquired by the array camera, an information processing amount increases in removing the unwanted object.